managed by Field Marshal Josef Philipp Vukassovich () and Josip Kajetan Knežić respectively. Subsequent modifications were not as significant. The road was paved in 1950, when the last minor modifications of the route were executed. The route was distinguished by mile markers along the route, an obelisk in Karlovac marking the beginning of the road and a specially built gate in Senj marking its end. Most remarkably the original road included a stone bridge across three spans in Tounj, which was expanded during the reconstruction of 1845 and now has two levels. The upper level was destroyed during World War II, but it was rebuilt in the 1950s. Traffic volume Traffic is regularly counted and reported by Hrvatske ceste, operator of the road. Substantial variations between annual (AADT) and summer (ASDT) traffic volumes are attributed to the fact that the road serves as a connection to A1 motorway and D8 state road carrying substantial tourist traffic. Road junctions and populated areas See also Highways in Croatia Autocesta Rijeka - Zagreb Hrvatske autoceste Maps Sources D023 D023 D023